The present invention relates generally to sound signal analyzing devices and methods for creating a MIDI file or the like on the basis of input sounds from a microphone or the like, and more particularly to an improved sound signal analyzing device and method which can effectively optimize various parameters for use in sound signal analysis.
Examples of the conventional sound signal analyzing devices include one in which detected volume levels and highest and lowest pitch limits, etc. of input vocal sounds have been set as parameters for use in subsequent analysis of sound signals. These parameters are normally set in advance on the basis of vocal sounds produced by ordinary users and can be varied as necessary by the users themselves when the parameters are to be put to actual use.
However, because the input sound levels tend to be influenced considerably by the operating performance of hardware components used and various ambient conditions, such as noise level, during sound input operations, there arises a need to review the level settings from time to time. Further, the upper and lower pitch limits would influence pitch-detecting filter characteristics during the sound signal analysis, and thus it is undesirable to immoderately increase a difference or width between the upper and lower pitch limits. Unduly increasing the width between the upper and lower pitch limits is undesirable in that it would result in a wrong pitch being detected due to harmonics and the like of the input sound. In addition, because the conventional sound signal analyzing devices require very complicated and sophisticated algorithm processing to deal with the pitch detection over a wide pitch range, the processing could not be readily carried out in real time. Moreover, even for some of the parameters appropriately modifiable by the users, it is necessary for the users to have a certain degree of musical knowledge, and therefore it is not desirable for the users to have freedom in changing the parameters. However, because some of the users may produce vocal sounds of a unique pitch range far wider than those produced by ordinary users or of extraordinary high or low pitches, it is very important that the parameters should be capable of being modified as necessary in accordance with the unique tendency and characteristics of the individual users.